THERE has always been a spirit of adventure about jazz quartet Empirical, which has won them critical praise and a clutch of awards, even if it has made them harder to sell to the wider public.

Winners of a presigious MOBO Award (for best Jazz Act) and described by the music press as ‘fascinating and fearless’ as well ‘the coolest of Britain’s young jazz bands’ Empirical look to push musical boundaries with each release.

For their fourth album, Tabula Rasa, that meant the introduction of strings and an upgrading of the foursome’s compositional skills to accommodate their ambitions.

You can hear the results when they perform at Birmingham Symphony Hall later this month.

Bass player Tom Farmer says that it’s a rare chance to see the project performed live.

“With this particular album, touring has had to be a bit more sporadic than we would have liked because we have to bring a string quartet with us.

“But this is a fantastic venue, the perfect place for this kind of thing – it was one of six places we indentified as being perfect for this project, so we are super excited about doing it.

Never a band to shy away from taking risks, Tabula Rasa is a double album that marks yet another new direction from Empirical, the next chapter in their developing story, consolidating ideas first explored on their previous albums Out ’n’ In (2009) and Elements of Truth (2011).

The line-up remains the same as the previous two albums with Nathaniel Facey, alto saxophone, Shaney Forbes, drums, and Lewis Wright, vibraphone, joining Tom.

But this time the sound is augmented by strings from the Benyounes Quartet, who the band met during a tenure as jazz scholars at the Trinity Laban Conservatoire of Music and Dance.

Tom says the use of strings had been in the band’s mind for a number of years, but Empirical were keen to avoid just ‘adding’ strings to their sound and instead treated them as a compositional tool with each piece exploring a different concept of the string quartet tradition.

Tom says: “We have always been intrigued by different musical traditions, it is how we operate. We are influenced by lots of musical styles rather than having a set agenda about what we play.

“We needed to take lessons in writing for strings and used that to try a few things out. We ended up with nine pieces on the album and we thought then it would be lovely to play the music in some nice halls up and down the UK.

“It was a real challenge but we agreed between us that we didn’t just want to do the usual Empirical stuff but with a few nice strings in the background. So we wrote all new music, which is difficult for people not experienced in writing for string quartets - but that was the point. It’s what we learn from all that which will stay with us through future projects.

Experimentation and observation have always been the Empirical ethos and that explains the band’s name.

“That’s the definition of Empirical, gathering knowledge through experimentation and observation,” says Tom. “Everything we do is an experiment, we never know at the start what is going to come out of these things.

“The aim is to enrich our musical voice and improve us as a band.

“We work well as a unit but rather than being a natural fit we had to work at it.

We have learnt each other’s way of playing. We know what kind of things we want to express. We are also all equal in the musical direction of the band.”

The 2010 Mobo Awards success put Empirical on the radar of a lot of music writers but didn’t eally boost album sales.

Tom says: “Our relationship with awards has been up and down. In the early days we attracted a lot of attention for what we were doing including the MOBO success. But that award was a bit of a paradox for us.

“People who were interested in the MOBO Awards don’t go to jazz gigs and those who do go to jazz gigs don’t pay attention to the MOBOs.

“So it had no tangible effect in terms of selling albums or tickets, although the good press it created helped get our name out there.”

The desire to avoid being pigeonholed means that Empirical have had more freedom to experiment but also ensures that they don’t provide an easy pathway in for new fans.

Tom says: “It’s easier to be sold by offering a pigeonhole for people to put you in but that unfortunately isn’t what we do. We are always trying to get away from that. The title of the new abum is a challenge to that whole mentality.”

Indeed, Tabula Rasa is Latin for ‘blank slate’ and invites the listener to approach the music with an open mind, free of preconception, and to draw from it what they will.

Tom says: “We have been labelled many times and either they have been incorrect or temporary. It’s an ongoing issue with our music but people do buy our records and come to our gigs, so something must be going right.”

Long-term that should also ensure that Empirical don’t have a flash-in-the-pan career where they peak and stagnate.

Tom says: “I think we have to experiment, that’s true of a lot of jazz groups but especially for us. It’s our role in the music world. We want to take risks. We are not here to make big money for big record labels, that’s not us.

“Our niche in the market is about experimenting and pushing boundaries. If that’s what we become known for then that’s fine - but it does make us hard to sell.”

- Tabla Rasa is out now on Naim Jazz Records – Empirical can be seen at Birmingham CBSO Symphony Hall on January 18. Go to www.empiricalmusic.com to buy tickets.